/*
 * Tencent is pleased to support the open source community by making
 * Hippy available.
 *
 * Copyright (C) 2022 THL A29 Limited, a Tencent company.
 * All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import type { HippyElement } from '../runtime/element/hippy-element';

/**
 * Set the class attribute to an element
 *
 * @param el - element
 * @param newValue - new value
 */
export function patchClass(el: HippyElement, newValue: string): void {
  let value = newValue;

  if (value === null) {
    value = '';
  }

  // directly setting className should be faster than setAttribute in theory
  // if this is an element during a transition, take the temporary transition classes into account.
  // the animation class will be processed later
  // const transitionClasses = (el as ElementWithTransition)._vtc;
  const transitionClasses = '';
  if (transitionClasses) {
    value = (
      value ? [value, ...transitionClasses] : [...transitionClasses]
    ).join(' ');
  }

  el.setAttribute('class', value);
}
